Selective oxidation of glycerol to 1,3-dihydroxyacetone by covalently immobilized glycerol dehydrogenases with higher stability and lower product inhibition

Immobilizing Systems Biocatalysis for the Selective Oxidation of Glycerol Coupled to In Situ Cofactor Recycling and Hydrogen Peroxide Elimination

“…Moreover, the mutant GlyDH was also stabilized by such immobilization and crosslinking chemistry as well as the wild-type variant reported recently by our group ( Figure S2). [27] Likewise, we have already reported that multipoint covalent immobilization and crosslinking through aldehyde chemistry stabilizes both NOX and CAT. [32,33] Therefore, the immobilization of such a trienzyme system on Ag-AG minimizes product inhibition and maximizes protein stability.…”

“…[34] On the other hand, the immobilization of GlyDH on the Ag-AG carrier seems to be optimal to minimize the product inhibition suffered by this enzyme. [27] Hence, by merging immobilization and protein engineering we have managed to reduce the inhibition of GlyDH by DHA and increase the thermal stability of all the enzymes that participate in the biotransformation simultaneously.…”

“…[25,26] Kinetics studies have revealed that DHA causes a noncompetitive inhibition on the GlyDH from Geobacillus stearothermophilus. [27] Reduction of DHA inhibition by engineering GlyDH…”

“…The X-ray structure and some kinetics studies of GlyDH from Geobacillus stearothermophilus (PDB code 1JQA) [27] enabled us to predict rationally some potential residues involved in the DHA binding. As well as other multimeric enzymes, we presume that GlyDH undergoes allosteric inhibition, although little is known about its allosteric site and its molecular mechanism.…”

“…[27] Both NOX and CAT were also immobilized individually on Ag-AG and further crosslinked with the same functional dextran polymer. The resulting insoluble and crosslinked preparations were used to oxidize glycerol with in situ NAD + recy- (Figure S1), whereas the same enzymes immobilized separately on Ag-AG and further crosslinked with dextran aldehyde produced DHA 2.4 times more rapidly ( Figure S1) to reach a final yield two times higher (2.8 mm) (Figure 4).…”